is mongodb relational database

MongoDB is a product between relational databases and non-relational databases. It has the most abundant functions and features like relational databases. It features high performance, easy to deploy, and easy to use, and stores data in a very convenient way.

Tags:date database updates nameget ways let Create end base SQLite--Embedded relational database 1. SQLite data type: typelessness (no type) 1, can save no matter what type of data to the table in the Random column 2. Supports common types such as: NULL, VARCHAR, TEXT, Integer, BLOB, CLOB, etc. 3, the only exception: integer primary key This field can only

Tags: des blog http using strong dataI believe that the development experience of friends have encountered such a demand. Suppose you are developing a comment function for a news site, and readers can comment on the original text or even reply to each other.This need is not simple, mutual reply will lead to an infinite number of branches, an infinite number of ancestor-descendant relationships. This is a ty

Tags: Big Data eraSqoop as a Hadoop The bridge between the traditional database and the data import and export plays an important role. by expounding the basic grammar and function of Sqoop, the paper deeply decrypts the function and value of Sqoop. First, what is Apache Sqoop?Clouderadeveloped byApacheOpen Source project, isSql-to-hadoopthe abbreviation. Mainly used inHadoop (Hive)with the traditional

Part i:relational Databases and SQLChapter2, ensuring Your Database Structureis sound.Database Design GuidelinesWhat is a relational databaseRDBMS (A relational database management systems) relational databaseTablesTables

is a right-to-left pop-up field, Lpop is a left-to-right pop-up field, Llen is a list of the lengths of the specified key Hash data type:127.0.0.1:6379[15]> Hmset member name Tom Age gender maleok# primary key and sub-key 127.0.0.1:6379[15]> hgetall member1) " Name "2)" Tom "3)" age "4)" 5 "[Gender] 6)" Male "#显示所有键值127 .0.0.1:6379[15]> hkeys member1)" name "2)"

Tags:merge class relationships rowidoutchar Two kinds of hash join length row The left Join,inner join that is often heard in development, right join, and cross join are logical connections to the database, so how does the database implement the associated table at the bottom when the database

be changed so that the transaction will still satisfy a+b=10, otherwise the transaction fails.3, I (isolation) IndependenceThe so-called independence refers to the concurrent transactions do not affect each other, if one transaction to access the data is being modified by another transaction, as long as another transaction is not committed, the data it accesses is